Software System Development Of Portable Ultrasonic Guided Wave Detector

Ultrasonic guided waves have the characteristics of long distance ability,low attenuation and so on.It has been widely used in the detection of defects such as large plates and pipes.At present,most of the ultrasonic guided wave detector on the market are foreign products.The technologies of these products are confidential,expensive,and mostly limited software functions.The software is not conducive to secondary development,and cannot meet the needs of user-defined.This dissertation mainly studies the FPGA logic design and upper software development of the portable ultrasonic guided wave detector.The main research work is as follows:(1)Based on developed instrument hardware,FPGA logic software for controlling the underlying hardware of ultrasonic waveguide instrument was developed.The control logic module for controlling the operation of the ultrasonic excitation circuit,the ultrasonic signal acquisition circuit and the signal amplification circuit is prepared,and the simulation test is carried out.All the modules are integrated together and downloaded to the actual hardware circuit for actual test.(2)A FIR digital filter based on FPGA is designed for the noise problem in the collected ultrasonic guided wave signals.Firstly,the FIR filter with parallel structure is designed and simulated with ModelSim and MATLAB software.According to the requirement of noise reduction in the actual ultrasonic guided wave signal,the designed filter is combined with the ultrasonic excitation and acquisition logic for the actual hardware test.The experimental results show that the designed filter can effectively suppress the noise in the collected signal and can be applied to the designed instrument system.(3)The instrument system drivers and application software is developed.The application software provides an operator interface for controlling the operation of the instrument,receiving control commands from the operator,and sending the control instructions to the underlying hardware control logic via the driver.The application software receives the collected data from the driver,and processes the collected data according to the operator's commands.Through the above work,the developed equipment can realize the following functions: Firstly,it can generate high voltage excitation pulse with adjustable amplitude and pulse width to adapt to different sensors.Secondly,the developed receiving module has a strong ability of digital signal processing and antijamming capability to acquire a useful signal to process.Thirdly,the device has a friendly and easy operation of the man-machine interface.Fourthly,the equipment have a considerable capacity of storage space to store the experimental data,with a common data interface,and the U disk and other mobile storage media can be used to transfer data to other devices.Fifthly,the device have a good secondary development function,with open programming interface,user-friendly data analysis and custom program development.Finally,the performance of the equipment was verified experimentally.